Liquid expressing press



Julie 1963 A. w. FRENCH ETAL 3,092017 LIQUID EXPRESSING PRESS 5 Sheets-Sheet 1 Filed Aug. 2, 1960 June 4, 1963 A. w. FRENCH ET AL 30 7 LIQUID EXPRESSNG PRESS 3 Sheets-Sheet 2 Filed Aug. 2, 1960 INVENTORS ET N mm WW T AE W June 4, 1963 A. w. FRENCH ETAL 3,

LIQUID EXPRESSING PRESS 3 Sheets-Sheet 3 Filed Aug. 2, 1960 tres This application relates t liquid expressing presses of the continuous type in which bulk material such as sucrose hearing fibrous materials (i.e. sugar cane, sugar beets, etc.) as well as ether meals, nu-ts, and the like oan be snbjected to high relatively continuous pressure-s, for example in the order of five to six thousand p.s.i. 0r higher, with the sucrose, juice, oils, or the like heing expressed therefirom and collected apart frorn the relatively dry expressed bulk which is discharged from the press.

A preferred type of screw press construction for this purpose nvolves -a cage including sereen bars in the Walls thereof which define Ininute openings through which the liquid may pass while containing the solids within the cage under the relatively high pressures. A rotery driven shaft extends through the cage and on this shaft are monnted alternately feeding or pressnre worms and pressure collars, eadh of which may or may not he tapered radially ontward in a direction from the inlet toward the dischazrge end of the oage, depencling upon the particu- 1ar action desired in that segment of the cage in which the particular flight and/or collar is located. In the area of the collars, projecting from the cage well toward the surfaces of the collar, there is at least one breaker bar or lug which resists rotation of the compacted material in this area and thus causes the material t0 pass axially throngh the press, in response to the pressure exerted thereon by the precedng worm flight. Generally speaking, the cross sectionai area of the passage through the press, hetween the sage walls and the worms and collars around the shaft, decreases from the inlet to the discharge end of the cage, and the pressures exerted will increase, into the neighborhood of, for example 10,000 p.s.i. in the portions of the passage of considerably lesser cross-sectional area.

In these areas the material becornes much drier and harder, since considerable liquid has been expressed, and suficient horsepower must be applied to the shaft earrying the worms and collars to overcome the friction between the hard material and the rotating sha:tt parts. As the pressure in the Gage increases, the frictional load increases proportiona-tely. The breaker bars located adjacent to the collars prevent the rotation of the material as it passes over the collars and this insures a frictional load hetween the rotating collar and the non-rotating material. This frictional load is responsive for a great porton i0f the power required to turn the shaft.

Accordingly, the primary object of this invention is to provide an irnproved liquid expressing press construction in which the frictional force exerted upon the collars by the material passing thereover is considerably reduced by eliminating the frictional component due to the ro-ta tien of the collar With respect to the material.

Another object of this invention is to provide such a press construction wherein the spacer collars between pressure worms are essentially free to rotate npon the shaft, and wherein hearing surfaces are provided between the shaft and such collans, including if desired anti-friction hearings.

Another object of this invention is to provide a stationary discharge collar about the shaft at the discharge end of the press cage, and preferably monnted from. the cage and adjustable with respect thereto along the axis of the 3092017 Patented June 4, 1963 shaft such as to control the disoharge areas at the end of the press through which the mater-ial is expelled.

An additional object of the invention is to provide such a discharge collar with drainage conneotions providing for removal of expressed liquid through the stationary diseharge collar as well as through the openings in the walls of the press cage.

A further object of the invention is to provide in the mountings of such stationary discharge collar a connection whereby the collar may be withdrawn well to the outside of the press to release pressure on the material in the event that it is necessary to shut down the press for sorne period of time and then to start again.

Another object of this invention is to provide a novel arrangement for flushing fonts and the like from the discharge collars.

A further object of the invention is to provide novel cooiing arrangements for a high pressure expressing press.

An additional object of the invention is to provide a novel discharge collar arrangement through which 1iquids can be flowed in a direction to provide addition or impregnation of liquid into the relatively dry material, within the press, from which liquid has been expressed.

Another object of the invention is to provide apparatus f0r burning losse plugs of dry material which may form adjacent the press discharge, particularly during starting of the press.

0ther 0bjects and adv-antages of the invention will be apparent from the following description, the accompanying drawings and the appended claims.

In the drawings:

FIG. 1 is a somewhat diagrarmamtic view in the form of a longitudinal section, with some parts shown in eleva tion, thron-gh essential parts of an expressing press in accordance with the invention;

FIG. 2 is an enla-rged sectional view of a portion of the press, illustrating the mounting of the collars and discharge sleeve within the press;

FIG. 3 is a detail sectonal view taken on line 3-3 of FIG. 2;

FIG. 4 is a sectional view taken on line 44 of FIG. 2;

F168. 5 and 6 are fragmentary views illustrating optional features of the invention;

FIG. 7 is a section taken on line 77- of FIG. 5;

FIG. 8 is a section taken on line 8-8 of FIG. 6;

FIG. 9 is a view of a modified construction generally similar to FIG. 6; and

FIGS. 10 and 11 are, respectvely, a longitudinal section and a cross-section view showing another modification.

Referring to the drawings, and particularly to FIGS. 1-4, the liquid expressing press includes a n1ain cage 10 which is made -up of complementary halves forrning a generally cylindrical elongated chamber 12. Per example, the cage may include semi-cylndrical halves 13 and 14, as shown particularly in FIG. 4, which are suitably bolted together when the press is in an operative condition. The drainage spaces are provided by a series of sereen bars 15 which are sutably supported in the cage sections and separated by spacers (not shown) which define minute spaces between the bars at the inner surfaces thereof through which expressed liquid may pass to the exterior of the cage, where it is collected in a pan or the like beneath the cage in well known manner.

A rnain shaft 20 extends coaxially through the press cage and is rotated by a suitable drive mechanism indicated schematically at 21. At the inlet end of the cage there is monnted a housing 22 including an inlet opening 23 through which liquid hearing materals are supplied, and also including a feed chamber 24 of generally cylindrical shape which is aligned with and opens into the inlet end of the main cage. Surrounding the shaft 20 in this area is a feed worm 25 which is rotatable independently thereof by a separate, nsually faster rotating, connection With the drive, including at least. one driving lug or dog 26.

Within the body of the cage, mounted on shaft 24), are alternately arranged collars 30 and eed or pressure worm bodies 32 each having a worm flight 33 extending into close proxirnity With the interior wall of the Gage. Adjacent the discharge end a discharge collar 35 is mounted through a supporting bracket 36 which is fastened to the cage structure and includes adjusting bolts 37 and spacers 38 providing a means for adjusting the position of the tapered discharge collar or sleeve along the length of the shaft to vary the cross-sectional area of the discharge opening which is defined by the collar and the surrounding ring 39 mounted also on the cage body. Relative movement between collar 35 and the preceding worm body is accommodated by an interfitting telescoping arrangement, indicated by the general reference numeral 40, or by any other suitable construction.

As shown particularly in -FIG. 2,. each of the coilars 30 and pressure worm bodies is a separate element. These collars may be of constant diameter as shown, er some of them have a tapered outer configuration, increasing in area toward the discharge end of the press to decrease accordingly the cross-sectional area through which the material must pass. The worm bodies 32 are connected fior driven movement with shaft 2t by means of keys 42, there being one key for each worm as shown. Surrounding the shaft withn each collar 39 there is a cylindrical spacer 43 which abuts the worm bodies to maintain proper spacing therebetween for free relative rotation between the worm bodies and collars 3G. Also, on the interior of each collar there is a hearing, which may be formed on the interior of the collar, or be a separate element, for example in the form of a separate sleeve 44. Thus, each of the collars 30 is capable of independent rotation upon the shaft 20, but is essentially confined against axial movement thereon by reason of its mounting between worm bodies 3.2. The last worm body is maintained in position by a threacled connection at 45 to the end of shaft 26, and this holds the entire assemblage fixed axially upon the shaft. Preferably, as shown in FIG. 2, the downstream (toward the discharge) ends of the collars are engaged with hardened thrnst Washers 47 Which abut the following worm body 32 and provide a hearing surface accommodating relative movernent between the adjacent worm and collar.

Accordingly, when shaft 29 is rotated by the drive, the worm bodies 32 will rotate therewith, and the worm flights 33 will force the material toward the following collars and succeeding worrns. As previously explained, due to the tapered configuration of the worm bodies (and/or collars) the downstream areas will be of lesser cross-section, and thus, such feeding action by the worm flights will produce an essentially sustained high mechanical pressure upon the material, expressing liquids therefrom, and the liquids will flow through the openings between the sereen bars to the exterior of the cage.

Where the material passes over collars 30, it is engaged by conventional breaker bars or lugs il which may be formed, for example, as extending pieces from a retainer plate or 'oar 52 secured to the cage by bolts 53 and serving also, in a preferred constrnction, to retain the stacked sereen bars in aligned abutting relation as shown. The breaker lugs will resist rotation of the compacted material and thus tend to force the material generally axially of the press toward the discharge end thereof. 'Since the collars are mounted such that the shaft can rotate relatively freely with respect to the collars, there is no power requred to rotate the collars against the friction of the compressed material being compacted against the collar surface. Thus, the action of the compressed material tending to retard any rotary rnovement of the collars (f there is any at ail) is not transmitted as a resistive force to the shaft, and it is therefore not necessary to supply power to the shaft for the purpose of overcorning such resistance to rotation.

Another feature of this construction is provided by the stationary mounting of the discharge collar 35', -wherein the supporting bnaeket 35 prevents rocation -therewithin. Since the areas of minimum cross-section are generally about this discharge collar, and at the disoharge orifice defined by this collar and the stationary discharge ring 39, the material is compacted nn-der very high pressnre and is present :as an essenti-ally solid plug. Reduetion of power needed to :overcome friction at t-hs location is also achieved in the same marmer as previously demoribed. In fact, probably the most significant power reduetion is made =awailable =through use of the non-rotating discharge coll-ar.

Fnrtherrnore, in the event that the press should be shut down under full load, =as by accident due to a cut-ofi of the power supply -to the drive, or :by necessity dne to sorne breakage, the cake surrounding the disolratrge oollar 35 becomes so hard that a great amount of power, per-haps in excess of the capabilities of the drive, is required to start again. Therefore, in many press constmctions it is n=ecessary -to open the cage and chip away this highiy compacted cake before stanting np again.

However, with the present invention it is possible o wi-thdraw the discharge collar 35 by releasing the bolts 37 and withdnawing the bracket 36. This will greatly increase the area of the discharge onifice, and the press can then easily be started, with the high pressnre adjacent he disclrarge relieved, end run empty until the hard cake is forced out, whereupon the disch=arge collar can be -returned te its operative position and the press mapidly put back into normal operation. If desired, instead Of ordinary bolts 37, special qnick releasing types may be pro vided, for example, ernbodying special heads of irregular slrape or the Jike which Will release the sleeve 35 when turned, thus provicling ior ready vvi thclrawal of the discharge collar.

It is also possible to control the enoss-sectional area hetween the collar 35 and the discharge ring 39, as prev-ionsly mentioned. This rnay conveniently be accom plished -by placing shims or the like of desired thickness in the area of the spacers 38, thus adjusting the final position of :collar 35 with respect to ring 39 when the bolts 37 are tightened. Obviously, equivalent aappanatus can be ntilized =for adjusting the eollarr 35 axially -to vary the discirarge opening.

With reference to FIGS. 5 and 7, rit is also possib=le to mount the collars independently of, but eligned over, the main drive straft. For example, as shown in these figures, split collars 30a can be provided with an internal diameter sornewhat greater than the diameter of shat 20, such that there is provision :for s-orne clearance therebetween, as shown particu-larly in FIG. 7. Bach half of these col lars can then be suitably aflixed, as by welding, te breaker lugs 50a which Will provide a convenient support for the colla-rs maintaining them stationary and in proper position within the press, Wthle the straft 20 een roate reely therewithin. If -it is not desired to use the breaker lngs for such mounting punposes, ether equivalent structure extending from the cage ean conveniently he provided in accordance wit-h the invention.

FIGS. 6 and 8 show a modified form of discharge coliar which may be used where additional drainage is desirable at the final high pressure area just before the discharge :orifice. In the particular embodiment shown the tapered discharge collar is net normally radiustable, and cooperates With a non-tapered stationary discharge ring 64 The last worm body 3212 is th-readed to the end of shaft 20, as shown in FIG. 6 and serves the further function of holding the previous worm bodies and collars axially -in =pl-ace upon the straft. The end 62 ofthe shafit is of reduced diameter, and is received withn and pro vidcs support for a sleeve hearing 65.

This hearing is in turn reeeived in the end of the discharge collar body 68, which body is hollow and preferably is provided with a closure cap or cover 69. A section of the surfiace of body 68 is undercut for supponting sereen bars, as indieated generally at 70 in FIG. 8. Inwardly of this seotion the hollow collar body is provided with radial openings 72 of substantial length, tmaversed by sol-id sections or pieces 73. A plurality of. short sereen bars 75 are placed about the collar body 68 within the seotion 70, and these sereen bars are separated by conventional spacers as shown generally at 76. These bars are held in place by a wedge b:ar 78 .at each side which is bolted into one of the solid segments 73. The collar body 68 is in turn threaded to an elongated ho1low sleeve member 80, and -thus there is an internal passage for expressed liquids conveyin-g such liquids to the exterior, beyond the end bracket or plate 82. This bracket is in turn secured to the supporting bracket 36a (of essentially the same construetion as pre-viously shown) by bolts 37a.

This construction provides for extra drainage opening in the area of the fina1 discharge collar, Where the peak pressures are exented upon the material, and thus .a press s0 constructed is capable of draning away more liquid without any increase in complexity or size.

It is also possible -'to direct Washng -liquids into such a discharge collar to provide for a circulation of liquid within the discharge collar 68-80, as by conducting a flow of liquid thereinto, or the purpose of wash-ing fine pieces of fibrous material or foots which may fcend to pass through the openings 76 in some circurnstances and thus Iend to block such drainage through the discharge sleeve unless washed away.

This washing liquid may be provided fr.om any convenient source (not shown) either as fresh liquid such as water, er as liquid previously expressed in the oage, connected into a pipe 85 which extends interiorly of the discharge collar 68 and its mounting sleeve 80, and which is provided with a number ocf small spray openings in its end which will direct a spray of the supp=lied liquid against the exposed inside surfaces of the bars 75. Of course, if desired similar ar-rangernents may be built into the body of the discharge collar 68 per se, however the use of a removable pipe and spray head as shown provides a convenient apparatus for this purpose which may be readily withdrawn if n0t needed, or for maintenance.

On some occasions when the press has been stopped and is subsequently started it is possible that a hard plug of compressed material may form adjacent the discharge end, particularly around the discharge collar. Rather than stopping the press to free such an initially formed plug, for example in the manner previously described, it may be possible to heat the structure of the press in the regions of such plug to such a high temperature that the plug of material will be burned and freed. Of eourse, the type of material being processed in the expressing press will to some extent determine the advisability of such procedure. In instances where such initial burning away of a tight plug is possible, heat for this source may be conveniently provided, in combination with the discharge sleeve constructions shown either in FIG. 2 or 6, by introducing live steam from a suitable source thereof through a pipe 100 and directing such steam through a spray head or the like against the interior surfaces of the collar. The steam will then heat the collar to a temperature high enough to burn away portions of the plug orrned against the collar, and the plug will be reed. nstead of supplying steam it is also possible to supply a eombustible mixture through the pipe 100 and to ignite such mixture at the end of such pipe interiorly of the discharge collar, direeting the resultant flame and heat against the collar for the same heating purpose.

As noted, the provision of collars within which the shaft can rota te is significantly helpful in reducing friction of the compressed material against the collars within the press chamber, and this in mm results in a significant decrease in heat due to r ction. A press eonstruoted in accordance with the invention can, therfore, operate satisfactorily with materials which heretofore presented problerns due to ill eiects thereon from such heating. Furthermore, it is possible to provide passages 110 within the shaft 20, together with conventional rotary seals in the area of the end 62 of the shaft, by means of which cooling liquid can be circulated through the shaft 20 for cooling thereof, and suitable passages can also be provided in the discharge sleeve (as through sleeve 35) for further cooling in the area if desired.

A further modified construotion in accordance with this invention is shown in FIG. 9. Basically, this construction is of the same type as shown in FIGS. 6 and 8, but the stationary discharge collar, and the sereen bars thereof, are tapered inwardly toward the discharge end of the press instead of owtwardly. Thus, similar parts have been given the same reference numeral with the suflx a. This construction will provide for a relaxation of the mechanical pressure exerted upon the material passing over the stationary discharge collar, and the ma terial therefore will expand somewhat in this region. If it is desired, liquids such as washing water or other liquid, or cooking liquor, may be added at this point by supplying such liquids to the interior of the discharge collar through the pipe 120. Since the material between the walls of the oage body and the discharge collar is undergoing a stage of relaxing mechanical pressure, it will tend to soak up materials thus added and flowing radially outward through the sereen bars 75a.

FIGS. 10 and 11 show a further modification construeted in aocordance with the invention. It should be noted -that FIG. 10 is a sectional view taken on line .1010 of FIG. 11, and that the upper portion of FIG. 10, although it appears in vertical section, is actually a horizontal section rotated to simplify illustration of the construction. In this construction the man cage body shown as portions of frame 100, contains the main cage defining parts including breaker bars 102 and a ring 103 at the discharge end of the cage body mounted within frame par-ts 100. The rotating main shaft is not specifically illustrated in FIG. 10, but it will be understood that the pressure worms 105 are suitably affixed to such shaft for rotation therewith in a direction to force material toward the eage discharge, and the collar 107 is suitably mounted about the shaft, in alignment with the breaker bars 108. This collar may be free to rotate with respect to the shaft, in the same manner as previously described, if so desired.

On the opposite side of frame 100 there is a mounting plate 110 which is suitably secured to the frame in any suitable manner, and a pair of supporting bracket arms 112 (FIG. 11) extend rearwardly from the plate 110 and are aiixed thereto, as by welding. A cross-bracket plate 114 is fastened t0 members 112 by bolts 115, and this cross plate provdes a fixed mounting for a discharge collar support tube 118 which is astened to the cross plate 114 by welding to a mounting ring 119. The tube 118 provides a mounting for the discharge collar which is shown by the general reference numeral 120, and which includes a collar body 122 threaded onto the tube 118 and supported coaxially of the main shaft.

The forward end of the collar body 122 carries a cover and cl=amp plate 123 which serves also to retain in position a nurnber of sereen bars 125 mounted side by side about the body 122. These bars are spaced slightly rom each other by the usual spacers, such as previously mentioned in connection with FIG. 4, and expressed liquids thus can pass between the sereen bars and through the openings 127 in the body 122, to flow out-wardly through the tube 118 to a collection point.

Surrounding the discharge collar 120 is an axially adjustable discharge cone construction which includes a cone body 130 having a forward part fitted within the ring 103, and slidable therein. The rearward portion of this body is substantially enlarged, as shown, and is provided with openings 132 which are traversed by sereen bars 135. These sereen bars are also spaced apart by the usual spacers, and are held in piace by a clarnping plate 137, thus providing drainage in an outward direction for expressed 1iquids. Such liquids oan be collected in a trough 138 which is suitably mounted below the cone struoture, and the cake material from whch the liquid has been expressed will be discharged through the open ing 140 between the collar body 122 and the cone structure. A baflie 142 is provided on the cone structure to direct the discharged cake over the trough 138.

The size of opening 140 can be regulated by adjusting the cone body 130 axially with respect to the diseharge collar. .This adjustment is provided by a pair of hydraulic rams, one of which is shown in elevation in FIG. 10, including a cylinder body 145 and an extendng piston rod 147 whch is suitably secured to the rearmost section 148 of the discharge cone body. The ram cylinder is mounted in a bracket 150 which is suitably bolted to the supporting bracket plate 112, as shown in FIG. 10. As will be seen from FIG. 11, this ram structure is duplicated on the opposite side of the dscharge cone, and each ram may include conventonal provisions (not shown) for clamping the piston rods thereof in a fixed position after appropriate adjustrnent has been made.

Power for the rams is provided by a pump 155 including an operating handle 156, and having a discharge line 158 which is connected in conventional marmer to each of the hydraulic rams to direct hydraulic fluid under pressure thereto. 1'his arrangement provides a convenient means, through manipulaton of purnp 155, to adjust the size of dscharge opening 140, and to maintain such opening at a desired setting. The discharge cone construction, With its incorporated sereen bars, cooperates With the stationary discharge collar 120 to provide a maximum of drainage area adjacent the discharge of the press, where the highest mechanical pressures are usually exerted uponthe material from whch liquid is being expressed.

While the adjustable cone construction is described and illustrated (FIGS. and 11) in combnation with a stationary discharge collar, t should be understood that this cone construction, with a-dditional drainage provisions in particular, can also be used with a dscharge collar which is carried by, and rotates with, the main shaft, as is conventional in many screw press constructions. In such instance, the adjustable cone will cooperate with the rotating collar to form a discharge orifice or opening of variable size.

-Whle the forms of apparatus herein described constitute preferred ernbodiments of the invention, it is to be understood that the invention is not limited to these precise forrns of apparatus, and that changes may be made therein without departing frorn the scope of the invention which is defined in the appended claims.

What is claimed is:

1. In en expressing press having a cage body includng drainage openings in the walls thereof, a main drive shaft extending through said cage body, a plurality of pressure worms including supporting bodies mounted in spaced apart relation upon said shaft and worm flights extending into close proximity with the Walls of said cage, means providing a driving conneetion between said shaft and said worms for concurrent rotation thereof, collars mounted upon said shaft be-tween adjacent said pressure worms, bearings between any of said collars and said shaft providing for independent rotation of each collar 011 said shaft, spacer mernbers on said shaft located interiorly of said bearings maintaining the positioning of said Worm bodies axially of said shaft, stationary breaker lugs extending adjacent to said collars to resist rotation of material forced over said collars onder pressure from the precedng worm fiight, at least some of said pressure worm bodies and/or collars being tapered to increase in thickness toward the discharge end of said cage body to decrease the area through whch the material is passed, and drive means connected to rotate said shaft causing said worm fiights to force material through such areas of decreasing cross-section exerting an expressing force on the material.

2. In an expressing press having a cage body inciuding drainage openings in the walls thereof and having inlet and discharge openings at opposite ends thereof, said body being of uniform cross seetional dimension between its said inlet and discharge openings, a dscharge ring mounted at one end of said cage and defining said discharge opening, a main drive shaft extending through said Gage body, a plurality of pressure worm bodies mounted in spaced apart relation upon said shaft and having worm flights extending to adjacent the walls of said cage body, means providing a driving connection between said shaft and said worms for concurrent rotation thereof in a direction to force material toward said discharge openings, collars mounted upon said shaft between adjacent said pressure worms, breaker lugs extendng from said cage body adjacent to said collars to resist rotation of material passing over said collars under pressure from the preceding worm, means connected to rotate said shaft causing said worms to foree material through said body and over said collars thus exerting an expressing force on the material, a discharge collar having a major portion of its length located inside said cage body and being coaxial with said shaft, a portion of said discharge collar extendng into said discharge ring and forrning therewith the said discharge opening, at least one of said discharge ring and said discharge coliar having a surface tapered toward the other end cooperating to define the passage through which the pressed material is expelled, and means mounting said discharge collar in normally stationary position frorn said cage body providing for rotation of said shaft with respect to said discharge collar to reduce the power input necessary to rotate said shaft and to reduce heating of the material forced past said discharge collar.

3. In a continuous screw press of the type defined in claim 2, the combination wherein said stationary dscharge collar is a hollow body, and means defining drainage openings in said discharge collar for further drainage of lquids and the 1ike from the materal subjected to the higher pressures exerted on the material surrounding said discharge oollar near the discharge opening of said press.

4. In a continuous screw press as defined in claim 3, the combination including a means for directing a flow of washng liquid against portions of said drainage open ing defining means interiorly of said discharge collar :to flush the interior thereof of eollections of foots, sediment, and the like.

5. In a continuous screw press as defined in claim 2, means for cooling said stationary discharge collar from the diseharge end of said screw press, and means for cooling said rotating shaft from the opposite end of said shaft from said discharge collar.

6. In a continuous screw press of the character described the combination of a cage body having a disoharge opening, means for exerting pressure on material within said body and simultaneously conveying the material through said body and said discharge opening including a rotatable shaft and at least one pressure worm aifixed thereto, drive means for rotating said shaft, means cooperating with said worm and said cage body to resist the passage of material through said body provding for an increase of mechanical pressre upon the material as it is eonveyed throngh said body, a stationary discharge collar mounted coaxially with said shaft adjacent said discharge opening and cooperating therewith to define a discharge orifice, said dscharge collar being tapered to a smaller diameter at the end thereof closest to said disoharge opening providing for a releasing of the mechanical pressure exerted upon material passing about said discharge collar to said dscharge opening, means defining drainage openings in the walls of said cage body for passage of liquids expressed from the material to the exterior of said cage body, means defining openings in said discharge collar of suficiently small size to prevent the passage of substanial amounts of the material into said openings, and means supplying a low of washing liquid to said openings in said discharge collar for mixture with the material passing over said discharge collar.

7. In a continuous screw press as defined in claim 6, means for supplying stearn through said openings in said discharge collar for mixture With the material passing over said discharge collar.

8. In a continuous screw press of the character described the combination of a cylindrical cage body having inlet and discharge openings at opposite ends thereof and having drainage openings in the walls of said cage for passage of expressed liquids and the like, said cage body being constructed to retain therein material subjected to mechanical pressures of the order of 5000 to 6000 p.s.i. a rotatable shaft extending coaxially within said cage body, at least ons pressure worm driven by said shaft and rotating within said body with minimum clearance between said worm and the inner walls of said body, means for obstrueting rotation of the material Within said cage body downstream of said worm toward said discharge opening to present an obstruction to flow of the material and causing the creation of high mechanical pressures upon the material to express liquids and the like therefrom, a discharge collar within said cage body coaxially arranged witn respect to said shaft, means mounting said discharge collar frorn said cage body rnaintaining said discharge collar normally stationary to present a stationary surface about which the compressed material must pass prior to exit thereof from the cage body through said discharge opening, a circular discharge ring surrounding said discharge collar adjacent the end of said dscharge collar farthest down stream of said worm and engaged with said cage body at said diseharge opening to form with said discharge collar an orifice at said discharge opening through which material is discharged, said ring having a plurality of spaced screen bars mounted in slightly spaced relation therein to form discharge openings in said ring through which expressed liquids rnay pass, at least one of said discharge collars and said discharge ring having a portion tapering toward the other to provide a discnarge opening which is of less efiective cross sectional area than the cross seetional area defined by the parts of said discharge collar within said cage and the walls of said cage surrounding said discharge collar, and means included in the mounting of said ring providing for adustment of the position of said ring with respect o said discharge collar for changing the size of said orifice.

9. Apparatus as defined in claim S wherein a plurality of sereen bars are rn0unted in said discharge collar in slightly spaced relation to each other forming drainage openings into the interior of said discharge collar, and means for conducting fron1 said discharge collar liquids and the like expressed through such drainage openings into the interior of said discharge collar.

10. In an expressing press as defined in claim 2, means forming a mounting for said collars mounted upon said shaft including earing means providing for free rotation of said collars upon said shaft between adjacent said pressure worms.

11. in a continuous screw press having a cage body, a main drive shaft extending through said cage body, a plurality of pressure worms mounted in spaced apart relation on said shaft, means providing a driving connection between said shaft and said worms for concurrent rotation thereof, stationary breaker lugs extending from said cage body toward said shaft at locations between said worms to resist rotation of material passing from the preceding worm, collars mounted on said shaft for free rotation thereon and extending into closely spaced relation with the adjacent breaker lugs providing for free rnovernent of the collars With respect to said lugs, and drive means for rotating said shaft causing said worms t0 orce material through said body and over said collars without driving said collars in rotation.

12. In a contnuous screw press of the character described the combination of a cage body having a discharge opening defined by a circular discharge ring, said cage body being eonstructed to hold therein material under mechanical pressures of as much as 10,000 p.s.i. means for exerting high mechanical pressure upon material within said body and simultaneously conveying the material through said body and said discharge opening, said means including a rotatable shaft and at least one pressure worm aflxed thereto, drive means for rotating said shaft, means defining drainage openings in the walls of said cage body for passage of liquids expressed from the material to the exterior of said body, a stationary discharge collar inside said cage body coaxial With said shaft extending into said ring to define therebetween a discharge orifice, means mounting said discharge collar from said cage body maintaining said discharge collar normally stationary With respect to said rotatable shaft thereby reclueing the power requred to rotate said shaft and reducing frictional heat created in the materialbeing forced between said discharge collar and the walls of said cage body and thence through said ring, and means for heating said discharge collar to temperatures in the region of the combustion temperature of material being processed through said press to burn away hard plugs of pressed material from about said discharge collar to free such plugs and provide for subsequent continuous operation of said press and passage of the material beng processed therethrough.

13. In a continuous screw press as defined in claim 2, hearing means cafried by said stationary discharge collar and engaging said drive shaft to support said shaft adjacent said discharge ring.

Referenees Cited in the file of this patent UNITED STATES PATENTS 1,152,857 -Stehln Sept. 7, 1915 1,750,916 Anderson et al. Mar. 18, 1930 1,851191 Lang Mar. 29, 1932 2,664,814 Ahlborn Jan. 5, 1954 2,775191 Y0ud Dec. 25, 1956 2,966,112 Guettler Dec. 27, 1960 FOREIGN PATENTS 43,080 Switzerland Dec. 9, 1907 

12. IN A CONTINUOUS SCREW PRESS OF THE CHARACTER DESCRIBED THE COMBINATION OF A CAGE BODY HAVING A DISCHARGE OPENING DEFINED BY A CIRCULAR DISCHARGE RING, SAID CAGE BODY BEING CONSTRUCTED TO HOLD THEREIN MATERIAL UNDER MECHANICAL PRESSURES OF AS MUCH AS 10,000 P.S.I., MEANS FOR EXERTING HIGH MECHANICAL PRESSURE UPON MATERIAL WITHIN SAID BODY AND SIMULTANEOUSLY CONVEYING THE MATERIAL THROUGH SAID BODY AND SAID DISCHARGE OPENING, SAID MEANS INCLUDING A ROTATABLE SHAFT AND AT LEAST ONE PRESSURE WORM AFFIXED THERETO, DRIVE MEANS FOR ROTATING SAID SHAFT, MEANS DEFINING DRAINAGE OPENINGS IN THE WALLS OF SAID CAGE BODY FOR PASSAGE OF LIQUIDS EXPRESSED FROM THE MATERIAL TO THE EXTERIOR OF SAID BODY, A STATIONARY DISCHARGE COLLAR INSIDE SAID CAGE BODY COAXIAL WITH SAID SHAFT EXTENDING INTO SAID RING TO DEFINE THEREBETWEEN A DISCHARGE ORIFICE, MEANS MOUNTING SAID DISCHARGE COLLAR FROM SAID CAGE BODY MAINTAINING SAID DISCHARGE COLLAR NORMALLY STATIONARY WITH RESPECT TO SAID ROTATABLE SHAFT THEREBY REDUCING THE POWER REQUIRED TO ROTATE SAID SHAFT AND REDUCING FRICTIONAL HEAT CREATED IN THE MATERIAL BEING FORCED BETWEEN SAID DISCHARGE COLLAR AND THE WALLS OF SAID CAGE BODY AND THENCE THROUGH SAID RING, AND MEANS FOR HEATING SAID DISCHARGE COLLAR TO TEMPERATURES IN THE REGION OF THE COMBUSTION TEMPERATURE OF MATERIAL BEING PROCESSED THROUGH SAID PRESS TO BURN AWAY HARD PLUGS OF PRESSED MATERIAL FROM ABOUT SAID DISCHARGE COLLAR TO FREE SUCH PLUGS AND PROVIDE FOR SUBSEQUENT CONTINUOUS OPERATION OF SAID PRESS AND PASSAGE OF THE MATERIAL BEING PROCESSED THERETHROUGH. 